(CNN) -- A nationwide sweep by federal agents targeting the violent MS-13 street gang has resulted in hundreds of arrests, including 263 gang members, the U.S. Immigration and Customs Enforcement agency announced Friday.

Deception Island is one of Antarctica’s biggest surprises. Part of the South Shetland group, the island appears on the map as a broken ring or a “C” shape. But it is actually the collapsed, sunken cone of a still-active volcano.